Signal-lamp



W. N. BEST.

SIGNAL LAMP. APPLICATION FILED SEPT- 9, 1916.

Patented June 22, 1920.

UNITED STATES PATENT- orries.

WILLIAM N. BEST, OF BROOKLYN, NEW YORK, ASSIGNOR F ONE-FOURTH '10 CECILIA WUPPER, OF BROOKLYN, NEW YORK.

SIGNAL-LAMP,

A To all whom it may concern:

tion from some other source of light de-v creases the contrast between the appearance of the signal light in its turned-on and turned-off conditions. 7

In the common forms of colored signal lights, a sheet or plate of the desired color is interposed between the source of light and the observer. This may. be either a colored bulb inclosing the filament of an electrlc incandescent lamp, a colored sheet of celluloid or other transparent or translucent medium, or it may be a separate glass plate, lens or bulls-eye in front of the electric, acetylene, oil, gas, or other illuminant. Such slgnal lights are open to certain objections due to the fact that the colored glass or other medium is exposed to the view of the observer and appears of its characteristic color in the day-time or when illuminated from any source of light other than that of the light of the signal itself. When the signal is turned on in the presence of some other source of illumination, the colored glass which the observer sees does not appear radicallydifierent from what it does when the signal is' turned off. In both cases, it appears of the same color although of course it is somewhat brighter when illuminated by the source .of light of the signal itself. Often this difference in brightness resulting from the turn' ing on or turning oil of the signal light is not noticed and therefore the signal fails in the accomplishment of its purpose. It is often difficult to tell whether a signal light is turned on or off when viewed from a distance during dayli ht.

Under many con itions of use, the colored glass is fre uently broken so that the desired colored lig t rays are not given out when Specification of Letters Patent.

Patented June 22, 1920.

Application filed September 9, 1916. Serial No. 119,174.

thelight is turned on and as a result, serious accidents are liable to occur.

In my improved signal light, I employ a screen in the form of a diaphragm, sheet or plate between the colored medium and the observer, and of such a character that the colored medium is either entirely concealed from vlew, or so nearly concealed, that its color is inconspicuous under all conditions of illumination from outside sources only.

j This interposed screen is so constructed that it will appear highly illuminated and of the desired color when the signal light is turned on and the light rays pass from the source of llght through the colored medium to the screen. Thus, the appearance of the signal light even in bright daylight is radically different when the signal light is turned on from what it is when turnedoff. In one case, it is highly illuminated and brightly colored, while in the other case, it is dull and apparently opaque.

liable to be cracked or broken and. at the same time acts as a protector for the colored medium between it and the source of light. It is highly translucent when the light is burning at the opposite side but is sufii- The screen is of tough, flexible material so that it is not:

ciently opaque to prevent the light or 001- ored medium from being seen when the light is turned ofl".

My invention may be incorporated in signal lights employed for a great variety of purposes. For instance, it may be used to great advantage on automobiles to indicate to pedestrians or drivers of other vehicles that the vehicle carrying the signal is about stanly noticed by those for whose benefit the signal is operated.

My improved signal li ht may also be used in connection with rai road semaphore,

switch, and other signals, or on light houses, and may be used with constant, intermittent lights controlled manually or automatically and revolved, oscillated or held stationary. As previously indicated, the source of light may be of any kind suited for the particular purpose at hand.

Reference is to be had to-the accompanying drawings in which I have illustrated only a few of the various specific forms which my invention may assume. In these drawings, Figure 1 is a face view of a signal light constructed in accordance with my invention, a portion of the screen being broken away;

Fig. 2 is a central longitudinal section on the line 22 of Fig. 1;

Fig. 3 is a partial side elevation and partial section of a different form, and

Figs. 4 and 5 are plan and edge views, respectively, of a portion of a suitable screen and on a somewhat enlarged scale.

In the specific form shown in Figs. 1 and 2, I employ an incandescent electric filament as the source of light, the said filament being inclosed in the ordinary vacuum bulb 10. This bulb is shown as properly positioned in respect to a parabolic reflector 11 which latter is supported in a suit able case 12. The lamp is of a general form commonly employed on automobiles and may be mounted or supported in any suitable manner.

In front of the bulb I place a screen 13 in addition to or in place of the ordinary lens, glass plate or bulls-eye. This screen is preferably slightly elastic, highly flexible, comparatively tough and unaffected by the heat of the lamp or the action of the weather. It may be made of various different compounds, but a suitable one is formed of a gelatinous or gummy substance such as gelatin, or glue, to which is added glycerin and formaldehyde. Upon boiling this mass to evaporate the water, the remaining mass may be rolled into sheets suitable for my purpose although an additional coating of waterproofing material may be applied thereto if desired. A sufficient amount of coloring matter is incorporated in the substance so as to render the sheet sufiiciently opaque to prevent the bulb within the lamp from being seen.

If the sheet is to be used as the front of the lamp and separate and independent of any glass plate, the sheet may, if desired, be reinforced to better enable it to withstand the effect of pebbles or other objects striking against it. Such a reinforcement might be formed of a very coarse mesh of very thin wires 14: as indicated in Figs. 1 and In order to get a uniform distribution of light over the surface and to. increase the brilliancy, one surface of the screen may be provided with thin corrugations 15 as indicated in Fig. 5.

To get the desired color effect when an electric light is employed, it is not necessary to employ a color screen separate from the body of the electric light itself. The bulb may be coloredred, green or any other color desired for signaling purposes and when the current is turned on, the effect of this colored bulb in the rear of the screen will be to highly illuminate the latter and make it appear the same in color as the bulb.

Under some circumstances, it may be desired to illuminate a portion of the screen with one color and another portion of the screen with another color. As shown, the upper half of the bulb is coated green while the lower half is coated red so that the action of the parabolic reflector will be to give the appearance of corresponding colors on the upper and lower halves of the screen when the light is turned on. lVhen the light is turned off, the opacity of the screen prevents either the red or the green of the bulb from being seen.

The screen may be secured in place in any suitable manner. As shown, I employ a collar 16 held in place by suitable screws 17 and cooperating with a peripheral flange on the casing to form clamps for the peripheral portion of the screen.

As I have previously indicated, my invention is not dependent upon any particular character of illuminant nor any particular form of lamp body. In Fig. 3,

I have shown a lamp casing 18 having a curved mirror 19 at the back and in the rear of an acetylene burner 20. At the front of the casing is a door 21 serving to support a screen 22 and a colored medium 23. The screen may be of the same character as that heretofore described. The colored medium 23 may be in the form of a glass plate constituting the equivalent of the glass bulb of Figs. 1 and 2 so far as the production of the desired colored light rays is concerned. This glass plate 23 may be colored red, green, or any other desired shade and may have different parts of different colors, or may have letters, figures, arrows, symbols, or other indications of a color contrasting with that of the balance of the plate. The colored plate and screen may be supported closely adjacent to each other or spaced slightly apart and may be clamped in any desired or suitable manner.

As shown, the periphery of the screen is held between an inturned flange 24.- on the closure 21 and a clamping ring 25. The colored glass 23-is shown as having its periphery supported in a "ti-shaped collar 26 which may be soldered or otherwise held in place in the closure 21.

The forms hereinbefore described are merely examples of my invention and I wish it understood that they are to be c0n-.

sidered merely in an illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A signal lamp comprising a casing, signaling means within the casing, including a source of light and a colored medium, and a shield arranged in front of the signaling means and consisting of a tough substantially non-breakable, uniformly translucent flexible: sheet adapted to protect the signals from being injured by'missiles to obliterate the color of the said medium when the light of the signaling means is extinguished whereby the unlighted signal will be prevented from showing color when exposed to exterior light.

2. A signal lamp provided with a shield constituting afront wall for the signal and consisting of a tough substantially nonbreakable, uniformly translucent flexible sheet adapted to obliterate color when the signal lamp is extinguished to prevent the unlighted signal lamp, from showing a signal when exposed to exterior light, sald shield being also adapted to protect the signal lamp from being injured by missiles.

Signed at New York inthe county of New York and State of New York, this 8th day of September, A. D. 1916.

WILLIAM N. BEST. 

